Eyeworld

Supported by unrestricted educational grants from Alcon Laboratories, Bausch + Lomb, LENSAR, and Sightpath Medical 7 our ability to correct astigmatism because we will have inaccurate measures of the magnitude and axis of astigmatism. Postoperative strategies After cataract surgery, patients may have residual astigmatism or be under- or overcorrected. We can prescribe contact lenses or glasses, perform laser vision correction, implant a piggyback IOL, perform an IOL exchange, or perform arcuate incisions to correct these cases. I base my choice on the patient's corneal topography and residual refractive error. We prepare patients for the potential need for a second pro- cedure to fine-tune their vision if they have factors that may increase the chance of being off-target, such as patients who had previous refractive surgery, various corneal diseases, or very long or short axial lengths or those in whom it is difficult to determine the exact astigmatism magnitude or axis. If a patient's postoperative vision is off-target, I perform a comprehensive examination, including topography and an OCT of the macula because there could be a new onset of mild macular swelling. We need to identify and treat that early, as well as dry eye and meibomian gland dysfunction (MGD) that may be present. One major controversy is whether we should perform a YAG before PRK or LASIK enhance- ments. If we perform a YAG, it might impact our ability to perform an IOL exchange in the future. However, in most cases I feel confident that optimizing the refractive error will result in a satisfied patient, so I tend to perform a YAG before PRK or LASIK. That is because there can be a shift in the refractive error following YAG. If we perform LASIK or PRK first and perform a YAG 6 months later, the patient's vision may be off-target. After treating dry eye and MGD and performing a YAG, I repeat corneal topography and refraction before performing the laser vision correction enhance- ment. With multifocal IOLs, we usually aim for plano. With an accommodative IOL, our goal may be slight myopia. Conclusion To optimize success with LACS, a thorough preoperative assessment is essential. If patients have post- operative residual refractive error, we need to optimize the ocular surface and consider performing YAG before laser vision correction. When weighing enhancement options, surgeons should consider the patient's residual refractive error, refractive surgery history, and corneal topography. Reference 1. Rabinowitz M. Keratoconus. Surv Ophthalmol. 1998;42:297–319. Dr. Trattler practices with the Center for Excellence in Eye Care, Miami. He can be contacted at wtrattler@ gmail.com. continued from page 6 continued from page 5 surgeons should educate their staff and patients about laser cataract surgery. If we do not speak confidently about it, they will not believe in it. We have to feel comfortable telling patients that we consider it better for their eyes. The only way to gain this confidence is to use it yourself and track your complication rates and outcomes. To obtain optimal results, surgeons should develop a surgical plan before surgery. We should not enter data on the fly. There is always the risk of transcription error, so surgeons and staff must be vigilant in their protocols and processes with surgical planning. For the procedure, patients should be lightly sedated; 1–2 mg of IV Versed is usually enough. If they are oversedated, they will fall asleep or wake during the proce- dure, causing a suction break. Because the laser can induce slight miosis, I place a drop of 10% phenylephrine in the eye after the laser procedure to dilate the pupil slightly as long as this is not a cardiac risk for the patient. Cortical cleanup is slightly different with femtosecond laser cataract surgery. Although it may appear that there is no cortex after the nucleus is removed, due to the presence of a perfectly clear red reflex, there may actually be a full untouched, undissected layer of cortex that is still present. A 360-degree whitish ring at the edge of the capsulotomy is the tipoff that there is still cortex there. Bimanual irrigation and aspiration can help remove the sticky cortex because the surgeon can switch hands for the subinci- sional space. Conclusion Femtosecond lasers offer clini- cal benefits for cataract surgery, including the creation of arcuate incisions and fragmentation of the lens. Surgeons should educate their staff and patients about what laser cataract surgery can offer. This technology continues to mature and will likely continue to prove its worth in delivering better refractive outcomes for patients undergoing cataract surgery. Reference 1. Abell RG, Kerr NM, Howie AR, Mustaffa Kamal MA, Allen PL, Vote BJ. Effect of fem- tosecond laser-assisted cataract surgery on the corneal endothelium. J Cataract Refract Surg. 2014; 40:1777–1783. Dr. Weinstock is in private practice at the Eye Institute of West Florida, Largo. He can be contacted at rjwein- stock@yahoo.com. Figure 2. Lens fragmentation patterns. Left: A basic 2-cut cross pattern used for soft cataracts. Right: More elaborate cube pattern used for denser cataracts.

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